The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent the work is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Referring now to FIG. 1, in a client-server network 100, a plurality of client computing devices 110-1, 110-2, . . . , and 110-C (collectively client computing devices or clients) communicates with a server computing device or server 120 via a distributed communications system (DSC) 108 such as the Internet or via a communication bus of a device, a local network, etc. Tasks or workloads are partitioned between the servers 120 (as providers of a resource or service) and the clients 110 (as service requesters). The servers 120 typically have a one to many relationship with the clients 110.
Client/server networks may use throttling mechanisms to limit performance based on a service level agreement (SLA) sold to a customer. Throttling mechanisms may also be used to prevent the client 110 from overloading the server 120 with too much work. Traditionally, this throttling is done on the request side of the client-server network 100. If the client 110 is trying to do more work than the throttle will allow, the client 110 is prevented from sending a new request.
When using request-side throttling, one of the clients (e.g. 110-1) has no knowledge of what the other clients (e.g. 110-1, . . . , 110-V) are doing. As such, the requests can needlessly collide and the overall efficiency of the client-server network 100 is reduced. In another example, two of the clients (e.g. 110-1 and 110-2) are both holding back requests in order to enforce their respective throttles. However, the server 120 is idle. Then the two clients 110-1 and 110-2 send requests to the server 120 at the same time. The server 120 receives both requests simultaneously. As such, one request must be delayed while the other request is processed.
In some examples, the clients 110 use a more advanced protocol in which the clients 110 ask for permission to send a request. The clients 110 then send the request when permission is granted by the server 120. However, this approach requires extra overhead relating to the request and the grant or denial of permission.